Silicon Heat-Dissipation Package For Compact Electronic Devices

ABSTRACT

Embodiments of a silicon heat-dissipation package for compact electronic devices are described. In one aspect, a device includes first and second silicon cover plates. The first silicon cover plate has a first primary side and a second primary side opposite the first primary side thereof. The second silicon cover plate has a first primary side and a second primary side opposite the first primary side thereof. The first primary side of the second silicon cover plate includes an indentation configured to accommodate an electronic device therein. The first primary side of the second silicon cover plate is configured to mate with the second primary side of the first silicon cover plate when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.

CROSS REFERENCE TO RELATED PATENT APPLICATION

The present disclosure claims the priority benefit of U.S. PatentApplication No. 61/887,426, filed on 6 Oct. 2013, which is incorporatedby reference in its entirety.

TECHNICAL FIELD

The present disclosure generally relates to the field of transfer ofthermal energy and, more particularly, removal of thermal energy fromcompact heat-generating devices.

BACKGROUND

There are many applications, ranging from consumer electronics totelecommunications and the like, in which compact electronic devicescapable of performing various tasks are packed in close proximity in asmall form factor to serve various needs. Such electronic devices mayinclude, for example, microprocessors, graphics processors, memorychips, global positioning system (GPS) chips, communications chips,laser diodes including edge-emitting lasers and vertical-cavitysurface-emitting lasers (VCSELs), light-emitting diodes (LEDs),edge-emitting laser diodes, radio frequency (RF) chips, microwave chips,photodiodes, sensors, etc. Electronic devices inevitably generatethermal energy, or heat, in operation and thus are heat sources, orheat-generating devices, during operation as well as for a period oftime after power off. As the number and complexity of thefunctionalities performed by electronic devices continue to increase,heat generated by any type of electronic devices as heat sources presenttechnical challenges that need to be addressed. For one thing,performance, useful lifespan, or both, of an electronic device may besignificantly impacted if the heat generated by the electronic device isnot adequately dissipated or otherwise removed from the compactelectronic device.

Metal heat sinks, lead frames and radiators, based on copper or aluminumfor example, have been a dominant heat sink choice for electronics andphotonics applications. However, as the form factor of compactelectronic devices gets smaller it is impractical to build a small metalheat sink with a large surface area heat sink to efficiently dissipateheat from compact electronic devices.

SUMMARY

Various embodiments disclosed herein pertain to a technique, design,scheme, device and apparatus related to a silicon heat-dissipationpackage for compact electronic devices as heat-generating devices.

In one aspect, a device may include first and second silicon coverplates. The first silicon cover plate may have a first primary side anda second primary side opposite the first primary side thereof. Thesecond silicon cover plate may have a first primary side and a secondprimary side opposite the first primary side thereof. The first primaryside of the second silicon cover plate may include an indentationconfigured to accommodate an electronic device therein. The firstprimary side of the second silicon cover plate may be configured to matewith the second primary side of the first silicon cover plate when thefirst silicon cover plate and the second silicon cover plate are joinedtogether with the electronic device sandwiched therebetween.

In at least some embodiments, the electronic device may be bonded to thesecond silicon cover plate by thermally-conductive epoxy or solder whenthe electronic device is accommodated in the indentation of the secondsilicon cover plate.

In at least some embodiments, the first silicon cover plate may includean opening communicatively connecting the first primary side and thesecond primary side of the first silicon cover plate. The opening may bealigned with the electronic device and exposing at least a portion ofthe electronic device when the first silicon cover plate and the secondsilicon cover plate are joined together with the electronic devicesandwiched therebetween.

In at least some embodiments, the device may further include acollimation element disposed in the opening of the first silicon coverplate and over the electronic device when the first silicon cover plateand the second silicon cover plate are joined together with theelectronic device sandwiched therebetween.

In at least some embodiments, the collimation element may include a lensmade of glass, silicone, quartz, or polymer.

In at least some embodiments, the second primary side of the firstsilicon cover plate may include first and second metallic patternsdeposited thereon and configured to electrically connect to first andsecond electrodes of the electronic device, respectively, when the firstsilicon cover plate and the second silicon cover plate are joinedtogether with the electronic device sandwiched therebetween.

In at least some embodiments, the second silicon cover plate may furtherinclude first and second vias on first and second sides of theindentation, respectively. The first and the second vias may be filledwith an electrically-conductive material and may correspond to the firstand the second metallic patterns on the first silicon cover plate toelectrically connect to the first and the second metallic patterns,respectively, when the first silicon cover plate and the second siliconcover plate are joined together with the electronic device sandwichedtherebetween.

In at least some embodiments, the device may further include a firstsilicon heat sink having a first primary side and a second primary sideopposite the first primary side thereof. The first primary side of thefirst silicon heat sink may be configured to mate with the secondprimary side of the second silicon cover plate when the first siliconheat sink and the second silicon cover plate are joined together.

In at least some embodiments, the first primary side of the firstsilicon heat sink may include first and second electrodes depositedthereon and corresponding to the first and the second vias of the secondsilicon cover plate to electrically connect to theelectrically-conductive material in the first and the second vias whenthe first silicon heat sink and the second silicon cover plate arejoined together.

In at least some embodiments, the second primary side of the secondsilicon cover plate may include third and fourth metallic patternsdeposited thereon and configured to electrically connect to the firstand the second electrodes of the first silicon heat sink, respectively,when the first silicon heat sink and the second silicon cover plate arejoined together.

In at least some embodiments, the first electrode of the first siliconheat sink may extend toward a first distal end of the first silicon heatsink and includes one or more first protrusions configured toelectrically connect to an external circuit board, and the secondelectrode of the first silicon heat sink may extend toward a seconddistal end of the first silicon heat sink opposite the first distal endand includes one or more second protrusions configured to electricallyconnect to the external circuit board.

In at least some embodiments, the second primary side of the firstsilicon heat sink may include a plurality of first grooves that form aplurality of first fins on the second primary side of the first siliconheat sink.

In at least some embodiments, the device may further include a secondsilicon heat sink having a first primary side and a second primary sideopposite the first primary side thereof. The second primary side of thesecond silicon heat sink may be configured to mate with the firstprimary side of the first silicon cover plate when the second siliconheat sink and the first silicon cover plate are joined together.

In at least some embodiments, the first primary side of the secondsilicon heat sink may include a plurality of second grooves that form aplurality of second fins on the first primary side of the second siliconheat sink.

In at least some embodiments, the first primary side of the firstsilicon cover plate may include a metal layer deposited thereon andconfigured to bond the first silicon cover plate and the second siliconheat sink.

In another aspect, a device may include first and second silicon coverplates, and may also include first and second silicon heat sinks. Thefirst silicon cover plate may include a first primary side and a secondprimary side opposite the first primary side thereof. The second siliconcover plate may include a first primary side and a second primary sideopposite the first primary side thereof. The first primary side of thesecond silicon cover plate may include an indentation configured toaccommodate an electronic device therein. The first primary side of thesecond silicon cover plate may be configured to mate with the secondprimary side of the first silicon cover plate when the first siliconcover plate and the second silicon cover plate are joined together withthe electronic device sandwiched therebetween. The first silicon heatsink may include a first primary side and a second primary side oppositethe first primary side thereof. The first primary side of the firstsilicon heat sink may be configured to mate with the second primary sideof the second silicon cover plate when the first silicon heat sink andthe second silicon cover plate are joined together. The second siliconheat sink may include a first primary side and a second primary sideopposite the first primary side thereof. The second primary side of thesecond silicon heat sink may be configured to mate with the firstprimary side of the first silicon cover plate when the second siliconheat sink and the first silicon cover plate are joined together.

In at least some embodiments, the first silicon cover plate may includean opening communicatively connecting the first primary side and thesecond primary side of the first silicon cover plate. The opening may bealigned with the electronic device and exposing at least a portion ofthe electronic device when the first silicon cover plate and the secondsilicon cover plate are joined together with the electronic devicesandwiched therebetween. The second silicon heat sink may include anopening communicatively connecting the first primary side and the secondprimary side of the second silicon heat sink and aligned with theopening on the first silicon cover plate. The device may further includea collimation element disposed in the opening of the first silicon coverplate and over the electronic device when the first silicon cover plateand the second silicon cover plate are joined together with theelectronic device sandwiched therebetween.

In at least some embodiments, the second primary side of the firstsilicon cover plate may include first and second metallic patternsdeposited thereon and configured to electrically connect to first andsecond electrodes of the electronic device, respectively, when the firstsilicon cover plate and the second silicon cover plate are joinedtogether with the electronic device sandwiched therebetween. The secondsilicon cover plate may further include first and second vias on firstand second sides of the indentation, respectively. The first and thesecond vias may be filled with an electrically-conductive material andcorresponding to the first and the second metallic patterns on the firstsilicon cover plate to electrically connect to the first and the secondmetallic patterns, respectively, when the first silicon cover plate andthe second silicon cover plate are joined together with the electronicdevice sandwiched therebetween. The first primary side of the firstsilicon heat sink may include first and second electrodes depositedthereon and corresponding to the first and the second vias of the secondsilicon cover plate to electrically connect to theelectrically-conductive material in the first and the second vias whenthe first silicon heat sink and the second silicon cover plate arejoined together. The second primary side of the second silicon coverplate may include third and fourth metallic patterns deposited thereonand configured to electrically connect to the first and the secondelectrodes of the first silicon heat sink, respectively, when the firstsilicon heat sink and the second silicon cover plate are joinedtogether.

In at least some embodiments, the second primary side of the firstsilicon heat sink may include a plurality of first grooves that form aplurality of first fins on the second primary side of the first siliconheat sink. The first primary side of the second silicon heat sink mayinclude a plurality of second grooves that form a plurality of secondfins on the first primary side of the second silicon heat sink.

In at least some embodiments, the device may further include theelectronic device accommodated in the indentation of the second siliconcover plate and sandwiched between the first and the second siliconcover plates. The electronic device may be at least partially configuredto function as a light-emitting diode (LED), a vertical-cavitysurface-emitting laser (VCSEL), an edge-emitting laser diode, a radiofrequency (RF) chip, a microwave chip, a photodiode, or a sensor.

In one aspect, a method may include: forming features of one or morefirst silicon cover plates on a first silicon wafer; forming features ofone or more second silicon cover plates on a second silicon wafer;forming features of one or more first silicon heat sinks on a thirdsilicon wafer; forming features of one or more second silicon heat sinkson a fourth silicon wafer; joining the first, the second, the third, andthe fourth silicon wafers into a stack of wafers with one or moreelectronic devices sandwiched between the first silicon wafer and thesecond silicon wafer; and dicing the stack of wafers to form one or moresilicon heat-dissipation packages each of which having a respective oneof the one or more electronic devices embedded therein. The first andthe second wafers may be sandwiched between the third and the fourthwafers. The first wafer may be adjacent the fourth wafer. The secondwafer may be adjacent the third wafer. The one or more first siliconcover plates, the one or more second silicon cover plates, the one ormore first silicon heat sinks, and the one or more second silicon heatsinks may be aligned with each other. Each of the one or more electronicdevices may be sandwiched between a respective one of the first siliconcover plates and a respective one of the second silicon cover plates.

In at least some embodiments, at least one of the one or more electronicdevices comprises an LED, a VCSEL, an edge-emitting laser diode, an RFchip, a microwave chip, a photodiode, or a sensor.

In at least some embodiments, forming features of one or more firstsilicon cover plates on the first silicon wafer may include forming anopening on each of the one or more first silicon cover plates. Theopening may communicatively connect a first primary side and a secondprimary side of the first silicon cover plate opposite the first primaryside. The opening may be aligned with a respective one of the one ormore electronic devices and may expose at least a portion of therespective electronic device.

In at least some embodiments, the method may further include disposingeach of one or more collimation elements in the respective opening of arespective one of the one or more first silicon cover plates.

In at least some embodiments, at least one of the one or morecollimation elements may include a lens made of glass, silicone, quartz,or polymer.

In at least some embodiments, forming features of one or more secondsilicon cover plates on the second silicon wafer may include forming anindentation on a primary side of each of the one or more second siliconcover plates. The indentation may be configured to accommodate arespective one of the electronic devices therein.

In at least some embodiments, forming features of one or more firstsilicon heat sinks on the third silicon wafer may include forming aplurality of first grooves that form a plurality of first fins on aprimary side of each of the one or more first silicon heat sinks facingaway from and not contacting a respective one of the one or more secondsilicon cover plates.

In at least some embodiments, forming features of one or more secondsilicon heat sinks on the fourth silicon wafer may include forming anopening on each of the one or more second silicon heat sinks. Theopening may communicatively connect a first primary side and a secondprimary side of the second silicon heat sinks opposite the first primaryside. The opening of each of the one or more second silicon heat sinksmay be aligned with the opening of a respective one of the one or morefirst silicon cover plates.

In at least some embodiments, forming features of one or more secondsilicon heat sinks on the fourth silicon wafer may include forming aplurality of second grooves that form a plurality of second fins on aprimary side of each of the one or more second silicon heat sinks facingaway from and not contacting a respective one of the one or more firstsilicon cover plates.

In at least some embodiments, forming features of the one or more firstsilicon cover plates on the first silicon wafer, forming features of theone or more second silicon cover plates on the second silicon wafer, andforming features of the one or more first silicon heat sinks on thethird silicon wafer may include forming electrically-conductive featureson each of the one or more first silicon cover plates, each of the oneor more second silicon cover plates, and each of the one or more firstsilicon heat sinks such that the respective electronic device in each ofthe one or more silicon heat-dissipation packages is configured to bepowered by an external power source through the electrically-conductivefeatures on the respective first silicon cover plate, the respectivesecond silicon cover plate, and the respective first silicon heat sink.

In another aspect, a method may include: joining first, second, third,and fourth silicon wafers into a stack of wafers with one or moreelectronic devices sandwiched between the first silicon wafer and thesecond silicon wafer; and dicing the stack of wafers to form one or moresilicon heat-dissipation packages each of which having a respective oneof the one or more electronic devices embedded therein. The first andthe second wafers may be sandwiched between the third and the fourthwafers. The first wafer may be adjacent the fourth wafer. The secondwafer may be adjacent the third wafer.

In at least some embodiments, the method may further include: formingfeatures of one or more first silicon cover plates on the first siliconwafer; forming features of one or more second silicon cover plates onthe second silicon wafer; forming features of one or more first siliconheat sinks on the third silicon wafer; and forming features of one ormore second silicon heat sinks on the fourth silicon wafer.

In at least some embodiments, the one or more first silicon coverplates, the one or more second silicon cover plates, the one or morefirst silicon heat sinks, and the one or more second silicon heat sinksmay be aligned with each other. Each of the one or more electronicdevices may be sandwiched between a respective one of the first siliconcover plates and a respective one of the second silicon cover plates.

In at least some embodiments, at least one of the one or more electronicdevices comprises an LED, a VCSEL, an edge-emitting laser diode, an RFchip, a microwave chip, a photodiode, or a sensor.

In at least some embodiments, the first silicon wafer may includefeatures of one or more first silicon cover plates thereon. The featuresmay include an opening on each of the one or more first silicon coverplates. The opening may communicatively connect a first primary side anda second primary side of the first silicon cover plate opposite thefirst primary side. The opening may be aligned with a respective one ofthe one or more electronic devices and exposing at least a portion ofthe respective electronic device.

In at least some embodiments, the method may further include disposingeach of one or more collimation elements in the respective opening of arespective one of the one or more first silicon cover plates.

In at least some embodiments, at least one of the one or morecollimation elements may include a lens made of glass, silicone, quartz,or polymer.

In at least some embodiments, the second silicon wafer may includefeatures of one or more second silicon cover plates thereon. Thefeatures may include an indentation on a primary side of each of the oneor more second silicon cover plates. The indentation may be configuredto accommodate a respective one of the electronic devices therein.

In at least some embodiments, the third silicon wafer may includefeatures of one or more first silicon heat sinks thereon. The featuresmay include a plurality of first grooves that form a plurality of firstfins on a primary side of each of the one or more first silicon heatsinks facing away from and not contacting a respective one of the one ormore second silicon cover plates.

In at least some embodiments, the fourth silicon wafer may includefeatures of one or more second silicon heat sinks thereon. The featuresmay include an opening on each of the one or more second silicon heatsinks. The opening may communicatively connect a first primary side anda second primary side of the second silicon heat sinks opposite thefirst primary side. The opening of each of the one or more secondsilicon heat sinks may be aligned with the opening of a respective oneof the one or more first silicon cover plates.

In at least some embodiments, the fourth silicon wafer may includefeatures of one or more second silicon heat sinks thereon. The featuresmay include a plurality of second grooves that form a plurality ofsecond fins on a primary side of each of the one or more second siliconheat sinks facing away from and not contacting a respective one of theone or more first silicon cover plates.

In at least some embodiments, forming features of the one or more firstsilicon cover plates on the first silicon wafer, forming features of theone or more second silicon cover plates on the second silicon wafer, andforming features of the one or more first silicon heat sinks on thethird silicon wafer may include forming electrically-conductive featureson each of the one or more first silicon cover plates, each of the oneor more second silicon cover plates, and each of the one or more firstsilicon heat sinks such that the respective electronic device in each ofthe one or more silicon heat-dissipation packages is configured to bepowered by an external power source through the electrically-conductivefeatures on the respective first silicon cover plate, the respectivesecond silicon cover plate, and the respective first silicon heat sink.

The proposed techniques are further described below in the detaileddescription section. This summary is not intended to identify essentialfeatures of the claimed subject matter, nor is it intended for use indetermining the scope of the claimed subject matter.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the disclosure, and are incorporated in and constitutea part of the present disclosure. The drawings illustrate embodiments ofthe disclosure and, together with the description, serve to explain theprinciples of the disclosure. It is appreciable that the drawings arenot necessarily in scale as some components may be shown to be out ofproportion than the size in actual implementation in order to clearlyillustrate the concept of the present disclosure.

FIG. 1 is a perspective view of a silicon heat-dissipation package for acompact electronic device in accordance with an embodiment of thepresent disclosure.

FIG. 2 is cross-sectional view of the silicon heat-dissipation packageof FIG. 1.

FIG. 3 is an exploded view of the silicon heat-dissipation package ofFIG. 1.

FIG. 4 is a perspective view of various silicon wafers that constitutevarious layers of the silicon heat-dissipation package of FIG. 1.

FIG. 5 is a perspective view of the various silicon wafers of FIG. 4assembled in a stack in the fabrication process of the siliconheat-dissipation package of FIG. 1.

FIG. 6 is a cross-sectional view of the stack of silicon wafers of FIG.5 along line BB.

FIG. 7 is a flowchart of a fabrication process of one or more siliconheat-dissipation packages in accordance with an embodiment of thepresent disclosure.

FIG. 8 is a flowchart of a fabrication process of one or more siliconheat-dissipation packages in accordance with another embodiment of thepresent disclosure.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS Overview

Various embodiments disclosed herein pertain to a technique, design,scheme, device and apparatus related to a silicon heat-dissipationpackage for compact electronic devices as heat-generating devices.Different from conventional techniques for heat dissipation for compactheat-generating devices in which metal heat sinks are used, embodimentsof the heat-dissipation package, or device, of the present disclosureare entirely or mostly made of silicon such as, for example,single-crystal silicon. For components of the silicon heat-dissipationpackage of the present disclosure that are made of silicon, detailedfeatures such as air cooling fins may be precision-made usingsemiconductor fabrication processes. Accordingly, components of thesilicon heat-dissipation package of the present disclosure may be massproduced with high precision with semiconductor fabrication processessuch as, for example, processes used in fabricatingmicro-electro-mechanical-system (MEMS) devices.

Example Embodiments

FIG. 1 illustrates a silicon heat-dissipation package for a compactelectronic device in accordance with an embodiment of the presentdisclosure. FIG. 2 is cross-sectional view of the siliconheat-dissipation package of FIG. 1. FIG. 3 is an exploded view of thesilicon heat-dissipation package of FIG. 1. Detailed description of aselect number of example embodiments are provided below with referenceto FIGS. 1-3.

In one aspect, device 1001, a silicon heat-dissipation package, includesa first silicon cover plate 13 and a second silicon cover plate 14. Thefirst silicon cover plate 13 has a first primary side (e.g., the sidefacing up in FIGS. 1-3) and a second primary side (e.g., the side facingdown in FIGS. 1-3) opposite the first primary side thereof. Similarly,the second silicon cover plate 14 also has a first primary side (e.g.,the side facing up in FIGS. 1-3) and a second primary side (e.g., theside facing down in FIGS. 1-3) opposite the first primary side thereof.The first primary side of the second silicon cover plate 14 includes anindentation that is configured to accommodate and receive an electronicdevice 10 therein. The first primary side of the second silicon coverplate 14 is configured to mate with the second primary side of the firstsilicon cover plate 13 when the first silicon cover plate 13 and thesecond silicon cover plate 14 are joined together with the electronicdevice 10 sandwiched therebetween. In at least some embodiments, thefirst silicon cover plate 13 and the second silicon cover plate 14 arejoined together by, for example, metal soldering, epoxy boding, eutecticbonding, anodic bonding, or diffusion bonding.

In at least some embodiments, the electronic device 10 is bonded to thesecond silicon cover plate 14 by thermally-conductive epoxy or solderwhen the electronic device 10 is accommodated in the indentation of thesecond silicon cover plate 14. The electronic device 10 may be at leastpartially configured to function as, for example, an LED, a VCSEL, anedge-emitting laser diode, an RF chip, a microwave chip, a photodiode,or a sensor. In general, the electronic device 10 is electricallypowered to perform its designed function(s) and, thus, generates heatduring its normal operation.

In at least some embodiments, the first silicon cover plate 13 includesan opening communicatively connecting the first primary side and thesecond primary side of the first silicon cover plate 13, e.g., a throughhole that traverses the thickness thereof. The opening is aligned withthe electronic device 10 and, therefore, is configured to expose atleast a portion of the electronic device 10 when the first silicon coverplate 13 and the second silicon cover plate 14 are joined together withthe electronic device 10 sandwiched therebetween. This feature isparticularly useful when the electronic device 10 is a type that emitsor detects light, whether visible or invisible, such as an LED, a VCSEL,a photodiode, a sensor, an RF chip or a microwave chip, for example.

In at least some embodiments, a sidewall of the opening on the firstsilicon cover plate 13 is approximately 90.0° as measured from ahorizontal plane that is parallel to the first primary side of the firstsilicon cover plate 13. In at least some other embodiments, the sidewallof the opening on the first silicon cover plate 13 is slanted or angled,in a cross-sectional view of the first silicon cover plate 13 as shownin FIG. 2, as measured from a horizontal plane that is parallel to thefirst primary side of the first silicon cover plate 13. That is, theangle as measured between the horizontal plane and the sidewall of theopening may be, for example, approximately 81.9°, 78.9°, 72.4°, 65.9°,60.0°, 54.7°, 45.0°, 37.6°, 35.3°, 31.4°, 30.0°, 25.2°, 15.8° or 11.4°.The angle depends on the crystal plane of the silicon wafer used infabricating the first silicon cover plate 13.

In at least some embodiments, the second primary side of the firstsilicon cover plate 13 includes an indentation such that, when the firstsilicon cover plate 13 and the second silicon cover plate 14 are joinedtogether, a slit exists between the first silicon cover plate 13 and thesecond silicon cover plate 14. This feature is particularly useful whenthe electronic device 10 is an edge-emitting laser diode because a laserbeam emitted by the electronic device 10, as an edge-emitting laserdiode, may be emitted out of the silicon heat-dissipation packagethrough the slit between the first silicon cover plate 13 and the secondsilicon cover plate 14. A collimating element may be disposed at or nearan opening of the slit to collimate the laser beam emitted from theedge-emitting laser diode.

In at least some embodiments, the device 1001 further includes acollimation element 11 disposed in the opening of the first siliconcover plate 13 and over the electronic device 10 when the first siliconcover plate 13 and the second silicon cover plate 14 are joined togetherwith the electronic device 10 sandwiched therebetween. When the sidewallof the opening on the first silicon cover plate 13 is angled, e.g., notvertical or 90° as measured from the horizontal plane (that is parallelto the first primary side of the first silicon cover plate 13) to thesidewall of the opening, the collimation element 11 is at leastpartially supported by the sidewall of the opening of the first siliconcover plate 13 as shown in FIG. 2.

In at least some embodiments, the collimation element 11 includes a lenswhich made of, for example, glass, silicone, quartz, or polymer.

In at least some embodiments, the second primary side of the firstsilicon cover plate 13 includes first and second metallic patterns 13 aand 13 b deposited thereon and configured to electrically connect tofirst and second electrodes 10 a and 10 b of the electronic device 10,respectively, when the first silicon cover plate 13 and the secondsilicon cover plate 14 are joined together with the electronic device 10sandwiched therebetween.

In at least some embodiments, the second silicon cover plate 14 furtherincludes first and second vias 14 a and 14 b on first and second sides(e.g., opposite sides) of the indentation, respectively. The first andthe second vias 14 a and 14 b are filled with an electrically-conductivematerial, e.g., metal, and correspond to, e.g., aligned with, the firstand the second metallic patterns 13 a and 13 b on the first siliconcover plate 13 to electrically connect to the first and the secondmetallic patterns 13 a and 13 b, respectively, when the first siliconcover plate 13 and the second silicon cover plate 14 are joined togetherwith the electronic device 10 sandwiched therebetween.

In at least some embodiments, the device 1001 further includes a firstsilicon heat sink 15 that has a first primary side (e.g., the sidefacing up in FIGS. 1-3) and a second primary side (e.g., the side facingdown in FIGS. 1-3) opposite the first primary side thereof. The firstprimary side of the first silicon heat sink 15 is configured to matewith the second primary side of the second silicon cover plate 14 whenthe first silicon heat sink 15 and the second silicon cover plate 14 arejoined together. In at least some embodiments, the first silicon heatsink 15 and the second silicon cover plate 14 are joined together by,for example, metal soldering, epoxy boding, eutectic bonding, anodicbonding, or diffusion bonding.

In at least some embodiments, the first primary side of the firstsilicon heat sink 15 includes first and second electrodes 15 a and 15 bdeposited thereon and corresponding to the first and the second vias 14a and 14 b of the second silicon cover plate 14 to electrically connectto the electrically-conductive material in the first and the second vias14 a and 14 b when the first silicon heat sink 15 and the second siliconcover plate 14 are joined together.

In at least some embodiments, the second primary side of the secondsilicon cover plate 14 includes third and fourth metallic patterns (notshown but similar to the first and second metallic patterns 13 a and 13b on the second primary side of the first silicon cover plate 13)deposited thereon and configured to electrically connect to the firstand the second electrodes 15 a and 15 b of the first silicon heat sink15, respectively, when the first silicon heat sink 15 and the secondsilicon cover plate 14 are joined together.

In at least some embodiments, the first electrode 15 a of the firstsilicon heat sink 15 extends toward a first distal end of the firstsilicon heat sink 15 and includes one or more first protrusions 16 a,e.g., a ball bump, configured to electrically connect to an externalcircuit board such as, for example, a printed circuit board. Likewise,the second electrode 15 b of the first silicon heat sink 15 extendstoward a second distal end of the first silicon heat sink 15 oppositethe first distal end and includes one or more second protrusions 16 b,e.g., a ball bump, configured to electrically connect to the externalcircuit board.

In at least some embodiments, the second primary side of the firstsilicon heat sink 15 includes a plurality of first grooves that form aplurality of first fins on the second primary side of the first siliconheat sink 15. Thus, surface area of the first silicon heat sink 15 isincreased multiple times with the grooves and fins on the second primaryside thereof, and this feature advantageously aids heat dissipation byconvection to the ambient air.

In at least some embodiments, the device 1001 further includes a secondsilicon heat sink 12 that has a first primary side (e.g., the sidefacing up in FIGS. 1-3) and a second primary side (e.g., the side facingdown in FIGS. 1-3) opposite the first primary side thereof. The secondprimary side of the second silicon heat sink 12 is configured to matewith the first primary side of the first silicon cover plate 13 when thesecond silicon heat sink 12 and the first silicon cover plate 13 arejoined together. In at least some embodiments, the first silicon coverplate 13 and the second silicon heat sink 12 are joined together by, forexample, metal soldering, epoxy boding, eutectic bonding, anodicbonding, or diffusion bonding. The second silicon heat sink 12 includesan opening communicatively connecting the first primary side and thesecond primary side of the second silicon heat sink 12, e.g., a throughhole that traverses the thickness thereof. The opening on the secondsilicon heat sink 12 is aligned with the opening on the first siliconcover plate 13 so as to expose at least a portion of the electronicdevice 10 to allow, for example, emission or detection of light by theelectronic device 10. The size of the opening on the second silicon heatsink 12 may be the same as or different from the size of the opening onthe first silicon cover plate 13, depending on the need in actualimplementation.

In at least some embodiments, the first primary side of the secondsilicon heat sink 12 includes a plurality of second grooves that form aplurality of second fins on the first primary side of the second siliconheat sink 12. Thus, surface area of the second silicon heat sink 12 isincreased multiple times with the grooves and fins on the second primaryside thereof, and this feature advantageously aids heat dissipation byconvection to the ambient air.

In at least some embodiments, the first primary side of the firstsilicon cover plate 13 includes a metal layer deposited thereon andconfigured to bond the first silicon cover plate 13 and the secondsilicon heat sink 12.

In another aspect, the device 1001 includes first and second siliconcover plates 13 and 14, and also includes first and second silicon heatsinks 15 and 12. The first silicon cover plate 13 includes a firstprimary side and a second primary side opposite the first primary sidethereof. The second silicon cover plate 14 includes a first primary sideand a second primary side opposite the first primary side thereof. Thefirst primary side of the second silicon cover plate 14 includes anindentation configured to accommodate and receive the electronic device10 therein. The first primary side of the second silicon cover plate 14is configured to mate with the second primary side of the first siliconcover plate 13 when the first silicon cover plate 13 and the secondsilicon cover plate 14 are joined together with the electronic device 10sandwiched therebetween. In at least some embodiments, the first siliconcover plate 13 and the second silicon cover plate 14 are joined togetherby, for example, metal soldering, epoxy boding, eutectic bonding, anodicbonding, or diffusion bonding. The first silicon heat sink 15 includes afirst primary side and a second primary side opposite the first primaryside thereof. The first primary side of the first silicon heat sink 15is configured to mate with the second primary side of the second siliconcover plate 14 when the first silicon heat sink 15 and the secondsilicon cover plate 14 are joined together. In at least someembodiments, the first silicon heat sink 15 and the second silicon coverplate 14 are joined together by, for example, metal soldering, epoxyboding, eutectic bonding, anodic bonding, or diffusion bonding. Thesecond silicon heat sink 12 includes a first primary side and a secondprimary side opposite the first primary side thereof. The second primaryside of the second silicon heat sink 12 is configured to mate with thefirst primary side of the first silicon cover plate 13 when the secondsilicon heat sink 12 and the first silicon cover plate 13 are joinedtogether. In at least some embodiments, the first silicon cover plate 13and the second silicon heat sink 12 are joined together by, for example,metal soldering, epoxy boding, eutectic bonding, anodic bonding, ordiffusion bonding.

In at least some embodiments, the first silicon cover plate 13 includesan opening communicatively connecting the first primary side and thesecond primary side of the first silicon cover plate 13. The opening isaligned with the electronic device 10 and exposes at least a portion ofthe electronic device 10 when the first silicon cover plate 13 and thesecond silicon cover plate 14 are joined together with the electronicdevice 10 sandwiched therebetween. The second silicon heat sink 12includes an opening communicatively connecting the first primary sideand the second primary side of the second silicon heat sink 12. Theopening on the second silicon heat sink 12 is aligned with the openingon the first silicon cover plate 13. The size of the opening on thesecond silicon heat sink 12 may be the same as or different from thesize of the opening on the first silicon cover plate 13, depending onthe need in actual implementation. The device 1001 further includes acollimation element 11 disposed in the opening of the first siliconcover plate 13 and over the electronic device 10 when the first siliconcover plate 13 and the second silicon cover plate 14 are joined togetherwith the electronic device 10 sandwiched therebetween. When the sidewallof the opening on the first silicon cover plate 13 is angled, e.g., notvertical or 90° as measured from the horizontal plane (that is parallelto the first primary side of the first silicon cover plate 13) to thesidewall of the opening, the collimation element 11 is at leastpartially supported by the sidewall of the opening of the first siliconcover plate 13 as shown in FIG. 2.

In at least some embodiments, a sidewall of the opening on the firstsilicon cover plate 13 is approximately 90.0° as measured from ahorizontal plane that is parallel to the first primary side of the firstsilicon cover plate 13. In at least some other embodiments, the sidewallof the opening on the first silicon cover plate 13 is slanted or angled,in a cross-sectional view of the first silicon cover plate 13 as shownin FIG. 2, as measured from a horizontal plane that is parallel to thefirst primary side of the first silicon cover plate 13. That is, theangle as measured between the horizontal plane and the sidewall of theopening may be, for example, approximately 81.9°, 78.9°, 72.4°, 65.9°,60.0°, 54.7°, 45.0°, 37.6°, 35.3°, 31.4°, 30.0°, 25.2°, 15.8° or 11.4°.The angle depends on the crystal plane of the silicon wafer used infabricating the first silicon cover plate 13.

In at least some embodiments, the second primary side of the firstsilicon cover plate 13 includes first and second metallic patterns 13 aand 13 b deposited thereon and configured to electrically connect tofirst and second electrodes 10 a and 10 b of the electronic device 10,respectively, when the first silicon cover plate 13 and the secondsilicon cover plate 14 are joined together with the electronic device 10sandwiched therebetween. The second silicon cover plate 14 furtherincludes first and second vias 14 a and 14 b on first and second sides(e.g., opposite sides) of the indentation, respectively. The first andthe second vias 14 a and 14 b are filled with an electrically-conductivematerial and correspond to the first and the second metallic patterns 13a and 13 b on the first silicon cover plate 13 to electrically connectto the first and the second metallic patterns 13 a and 13 b,respectively, when the first silicon cover plate 13 and the secondsilicon cover plate 14 are joined together with the electronic device 10sandwiched therebetween. The first primary side of the first siliconheat sink 15 includes first and second electrodes 15 a and 15 bdeposited thereon and corresponding to the first and the second vias 14a and 14 b of the second silicon cover plate 14 to electrically connectto the electrically-conductive material in the first and the second vias14 a and 14 b when the first silicon heat sink 15 and the second siliconcover plate 14 are joined together. The second primary side of thesecond silicon cover plate 14 includes third and fourth metallicpatterns (not shown) deposited thereon and configured to electricallyconnect to the first and the second electrodes 15 a and 15 b of thefirst silicon heat sink 15, respectively, when the first silicon heatsink 15 and the second silicon cover plate 14 are joined together.

In at least some embodiments, the second primary side of the firstsilicon heat sink 15 includes a plurality of first grooves that form aplurality of first fins on the second primary side of the first siliconheat sink 15. Similarly, the first primary side of the second siliconheat sink 12 includes a plurality of second grooves that form aplurality of second fins on the first primary side of the second siliconheat sink 12. Accordingly, surface areas of the first and the secondsilicon heat sinks 15 and 12 are increased multiple times with thegrooves and fins on the second primary side thereof, and this featureadvantageously aids heat dissipation by convection to the ambient air.

In at least some embodiments, the device 1001 further includes theelectronic device 10 accommodated and received in the indentation of thesecond silicon cover plate 14 and sandwiched between the first and thesecond silicon cover plates 13 and 14. The electronic device 10 may beat least partially configured to function as an LED, a laser diode suchas a VCSEL, an RF chip, a microwave chip, a photodiode, or a sensor.

In at least some embodiments, the second primary side of the firstsilicon cover plate 13 includes an indentation such that, when the firstsilicon cover plate 13 and the second silicon cover plate 14 are joinedtogether, a slit exists between the first silicon cover plate 13 and thesecond silicon cover plate 14. This feature is particularly useful whenthe electronic device 10 is an edge-emitting laser diode because a laserbeam emitted by the electronic device 10, as an edge-emitting laserdiode, may be emitted out of the silicon heat-dissipation packagethrough the slit between the first silicon cover plate 13 and the secondsilicon cover plate 14. A collimating element may be disposed at or nearan opening of the slit to collimate the laser beam emitted from theedge-emitting laser diode.

A core concept of the silicon heat-dissipation package of the presentdisclosure is that the heat-generating compact electronic device 10 issandwiched between the first silicon cover plate 13 and the secondsilicon cover plate 14 so that heat can be effectively and efficientlytransferred from the electronic device 10 to the first silicon coverplate 13 and the second silicon cover plate 14, at least by thermalconduction due to direct contacts therebetween. The siliconheat-dissipation package may optionally include either or both of thefirst silicon heat sink 15 and the second silicon heat sink 12 to aidspreading the heat away from the electronic device 10 and into ambientair and/or a thermal ground, e.g., a casing of an apparatus in which thesilicon heat-dissipation package is contained or an object to which thesilicon heat-dissipation package is attached.

Therefore, various implementations of the silicon heat-dissipationpackage may have different numbers of components. For instance, in oneimplementation, the silicon heat-dissipation package may include thefirst and the second silicon cover plates 13 and 14. In anotherimplementation, the silicon heat-dissipation package may include thefirst and the second silicon cover plates 13 and 14 as well as the firstsilicon heat sink 15. In yet another implementation, the siliconheat-dissipation package may include the first and the second siliconcover plates 13 and 14 as well as the second silicon heat sink 12. Instill another implementation, the silicon heat-dissipation package mayinclude the first and the second silicon cover plates 13 and 14 as wellas the first and the second silicon heat sinks 15 and 12.

As another example, in some implementations, the electrodes 10 a and 10b of the electronic device 10 may be on the side of the electronicdevice 10 facing and/or in contact with the second silicon cover plate14. Accordingly, there would be no need to deposit the metallic patterns13 a and 13 b on the second primary side of the first silicon coverplate 13 and, instead, there would be metallic patterns deposited on thefirst primary side of the second silicon cover plate 14 and extendingfrom the first and the second vias 14 a and 14 b, respectively, toprovide electrical connection from an external power source to theelectronic device 10. Alternatively, in some implementations, theelectrodes 10 a and 10 b of the electronic device 10 may be ondifferent, e.g., opposite, sides of the electronic device 10.Accordingly, there would be metallic patterns deposited on both thesecond primary side of the first silicon cover plate 13 and the firstprimary side of the second silicon cover plate 14 to provide electricalconnection from an external power source to the electronic device 10.

Embodiments of the silicon heat-dissipation package of described aboveembeds a single electronic device therein and, thus, may have an opening(i.e., through the first silicon cover plate and the second silicon heatsink) to expose at least a portion of the electronic device, e.g., foremission or detection purpose. In some implementations, however, asingle silicon heat-dissipation package in accordance with the presentdisclosure may embed multiple electronic devices therein. Accordingly,depending on the function of the electronics devices, the siliconheat-dissipation package may include one or more openings to expose atleast a portion of some or all of the multiple electronic devicesembedded therein. That is, one or more of the multiple electronicdevices embedded therein may need to be at least partially exposed,e.g., for emission or detection purpose, while one or more other ones ofthe multiple electronic devices embedded therein need not be exposed. Aswould be appreciated by those skilled in the art, the scope of theinventive concept of the present disclosure is not limited to and infact extends beyond those examples illustrated and described herein.

Example Processes

FIG. 4 illustrates various silicon wafers that constitute various layersof the silicon heat-dissipation package of FIG. 1. FIG. 5 is aperspective view of the various silicon wafers of FIG. 4 assembled in astack in the fabrication process of the silicon heat-dissipation packageof FIG. 1. FIG. 6 is a cross-sectional view of the stack of siliconwafers of FIG. 5 along line BB. Detailed description of a select numberof example embodiments are provided below with reference to FIGS. 4-6.

As shown in FIGS. 1-3, the silicon heat-dissipation package, or device1001, comprises of multiple layers of silicon components. Each of theselayers of silicon components may be a single piece of die of multipledies cut from a respective silicon wafer. Accordingly, as shown in FIGS.4-6, silicon wafers 21, 22, 23 and 24 are processed to producecomponents of the device 1001, namely the second silicon heat sink 12,the first silicon cover plate 13, the second silicon cover plate 14 andthe first silicon heat sink 15. Each of the silicon wafers 21, 22, 23and 24 is, for example, a wafer of single-crystal silicon. Silicon wafer21 is processed to include features that, when the silicon wafer 21 iscut into multiple piece of dies, will provide multiple instances of thesecond silicon heat sink 12. Silicon wafer 22 is processed to includefeatures that, when the silicon wafer 22 is cut into multiple piece ofdies, will provide multiple instances of the first silicon cover plate13. Silicon wafer 23 is processed to include features that, when thesilicon wafer 23 is cut into multiple piece of dies, will providemultiple instances of the second silicon cover plate 14. Silicon wafer24 is processed to include features that, when the silicon wafer 24 iscut into multiple piece of dies, will provide multiple instances of thefirst silicon heat sink 15.

In at least some embodiments, each of the silicon wafers 21, 22, 23 and24 are processed first, e.g., through some or all of the steps ofdeposition, photolithography, dry and/or wet etch andchemical/mechanical polishing, so that features of the respectivecomponent of the device 1001 are fabricated onto each of the siliconwafers 21, 22, 23 and 24. Then, as shown in FIGS. 5 and 6, the siliconwafers 21, 22, 23 and 24 are stacked and joined together, with multipleinstances of the electronic device 10 and the collimation element 11respectively sandwiched therebetween, before cutting. The silicon wafers21, 22, 23 and 24 are joined together by, for example, metal soldering,epoxy boding, eutectic bonding, anodic bonding, or diffusion bonding.When the stack of the processed silicon wafers 21, 22, 23 and 24 is cutinto multiple pieces of stacked dies, each of the stacked diesconstitutes a single instance of the device 1001, which is a siliconheat-dissipation device, with a respective electronic device 10 embeddedtherein.

In view of the above description with reference to FIGS. 4-6, thefollowing description pertains to a select number of embodiments afabrication process in accordance with the present disclosure.

FIG. 7 illustrates a fabrication process 700 of one or more siliconheat-dissipation packages in accordance with an embodiment of thepresent disclosure. Process 700 includes one or more operations,actions, or functions as illustrated by one or more of blocks 702, 704,706, 708, 710 and 712. Process 700 may be implemented in fabricating oneor more silicon heat-dissipation packages as shown in FIGS. 4-6.Although illustrated as discrete blocks, various blocks may be dividedinto additional blocks, combined into fewer blocks, or eliminated,depending on the desired implementation. Process 700 begins withoperation 702.

At 702, process 700 may form features of one or more first silicon coverplates on a first silicon wafer.

At 704, process 700 may form features of one or more second siliconcover plates on a second silicon wafer.

At 706, process 700 may form features of one or more first silicon heatsinks on a third silicon wafer.

At 708, process 700 may form features of one or more second silicon heatsinks on a fourth silicon wafer.

At 710, process 700 may join the first, the second, the third, and thefourth silicon wafers into a stack of wafers with one or more electronicdevices sandwiched between the first silicon wafer and the secondsilicon wafer. In at least some embodiments, the first, the second, thethird, and the fourth silicon wafers are joined together by, forexample, metal soldering, epoxy boding, eutectic bonding, anodicbonding, or diffusion bonding. In at least some embodiments, each of thefirst, the second, the third, and the fourth wafer is a wafer ofsingle-crystal silicon.

At 712, process 700 may dice the stack of wafers to form one or moresilicon heat-dissipation packages each of which having a respective oneof the one or more electronic devices embedded therein.

In joining the first, the second, the third, and the fourth siliconwafers into a stack of wafers with one or more electronic devicessandwiched between the first silicon wafer and the second silicon wafer,process 700 may result in the following: the first and the second wafersbeing sandwiched between the third and the fourth wafers; the firstwafer being adjacent the fourth wafer; the second wafer being adjacentthe third wafer; the one or more first silicon cover plates, the one ormore second silicon cover plates, the one or more first silicon heatsinks, and the one or more second silicon heat sinks being aligned witheach other; and each of the one or more electronic devices beingsandwiched between a respective one of the first silicon cover platesand a respective one of the second silicon cover plates.

In at least some embodiments, at least one of the one or more electronicdevices comprises an LED, a laser diode such as a VCSEL, an RF chip, amicrowave chip, a photodiode, or a sensor.

In at least some embodiments, in forming features of one or more firstsilicon cover plates on the first silicon wafer, process 700 may form anopening on each of the one or more first silicon cover plates. Theopening may communicatively connect a first primary side and a secondprimary side of the first silicon cover plate opposite the first primaryside. The opening may be aligned with a respective one of the one ormore electronic devices and may expose at least a portion of therespective electronic device.

In at least some embodiments, process 700 may further include disposingeach of one or more collimation elements in the respective opening of arespective one of the one or more first silicon cover plates.

In at least some embodiments, at least one of the one or morecollimation elements may include a lens made of glass, silicone, quartz,or polymer.

In at least some embodiments, in forming features of one or more secondsilicon cover plates on the second silicon wafer, process 700 may forman indentation on a primary side of each of the one or more secondsilicon cover plates. The indentation may be configured to accommodate arespective one of the electronic devices therein.

In at least some embodiments, in forming features of one or more firstsilicon heat sinks on the third silicon wafer, process 700 may form aplurality of first grooves that form a plurality of first fins on aprimary side of each of the one or more first silicon heat sinks facingaway from and not contacting a respective one of the one or more secondsilicon cover plates.

In at least some embodiments, in forming features of one or more secondsilicon heat sinks on the fourth silicon wafer, process 700 may form anopening on each of the one or more second silicon heat sinks. Theopening may communicatively connect a first primary side and a secondprimary side of the second silicon heat sinks opposite the first primaryside. The opening of each of the one or more second silicon heat sinksmay be aligned with the opening of a respective one of the one or morefirst silicon cover plates.

In at least some embodiments, in forming features of one or more secondsilicon heat sinks on the fourth silicon wafer, process 700 may form aplurality of second grooves that form a plurality of second fins on aprimary side of each of the one or more second silicon heat sinks facingaway from and not contacting a respective one of the one or more firstsilicon cover plates.

In at least some embodiments, in forming features of the one or morefirst silicon cover plates on the first silicon wafer, forming featuresof the one or more second silicon cover plates on the second siliconwafer, and forming features of the one or more first silicon heat sinkson the third silicon wafer, process 700 may form electrically-conductivefeatures on each of the one or more first silicon cover plates, each ofthe one or more second silicon cover plates, and each of the one or morefirst silicon heat sinks such that the respective electronic device ineach of the one or more silicon heat-dissipation packages is configuredto be powered by an external power source through theelectrically-conductive features on the respective first silicon coverplate, the respective second silicon cover plate, and the respectivefirst silicon heat sink.

FIG. 8 illustrates a fabrication process 800 of one or more siliconheat-dissipation packages in accordance with another embodiment of thepresent disclosure. Process 800 includes one or more operations,actions, or functions as illustrated by one or more of blocks 802 and804. Process 800 may be implemented in fabricating one or more siliconheat-dissipation packages as shown in FIGS. 4-6. Although illustrated asdiscrete blocks, various blocks may be divided into additional blocks,combined into fewer blocks, or eliminated, depending on the desiredimplementation. Process 800 begins with operation 802.

At 802, process 800 may join first, second, third, and fourth siliconwafers into a stack of wafers with one or more electronic devicessandwiched between the first silicon wafer and the second silicon wafer.In at least some embodiments, the first, the second, the third, and thefourth silicon wafers are joined together by, for example, metalsoldering, epoxy boding, eutectic bonding, anodic bonding, or diffusionbonding. In at least some embodiments, each of the first, the second,the third, and the fourth wafer is a wafer of single-crystal silicon.

At 804, process 800 may dice the stack of wafers to form one or moresilicon heat-dissipation packages each of which having a respective oneof the one or more electronic devices embedded therein. The first andthe second wafers may be sandwiched between the third and the fourthwafers. The first wafer may be adjacent the fourth wafer. The secondwafer may be adjacent the third wafer.

In at least some embodiments, process 800 may further include formingfeatures of one or more first silicon cover plates on the first siliconwafer; forming features of one or more second silicon cover plates onthe second silicon wafer; forming features of one or more first siliconheat sinks on the third silicon wafer; and forming features of one ormore second silicon heat sinks on the fourth silicon wafer.

In at least some embodiments, the one or more first silicon coverplates, the one or more second silicon cover plates, the one or morefirst silicon heat sinks, and the one or more second silicon heat sinksmay be aligned with each other. Each of the one or more electronicdevices may be sandwiched between a respective one of the first siliconcover plates and a respective one of the second silicon cover plates.

In at least some embodiments, at least one of the one or more electronicdevices comprises an LED, a laser diode such as a VCSEL, an RF chip, amicrowave chip, a photodiode, or a sensor.

In at least some embodiments, the first silicon wafer may includefeatures of one or more first silicon cover plates thereon. The featuresmay include an opening on each of the one or more first silicon coverplates. The opening may communicatively connect a first primary side anda second primary side of the first silicon cover plate opposite thefirst primary side. The opening may be aligned with a respective one ofthe one or more electronic devices and exposing at least a portion ofthe respective electronic device.

In at least some embodiments, the method may further include disposingeach of one or more collimation elements in the respective opening of arespective one of the one or more first silicon cover plates.

In at least some embodiments, at least one of the one or morecollimation elements may include a lens made of glass, silicone, quartz,or polymer.

In at least some embodiments, the second silicon wafer may includefeatures of one or more second silicon cover plates thereon. Thefeatures may include an indentation on a primary side of each of the oneor more second silicon cover plates. The indentation may be configuredto accommodate a respective one of the electronic devices therein.

In at least some embodiments, the third silicon wafer may includefeatures of one or more first silicon heat sinks thereon. The featuresmay include a plurality of first grooves that form a plurality of firstfins on a primary side of each of the one or more first silicon heatsinks facing away from and not contacting a respective one of the one ormore second silicon cover plates.

In at least some embodiments, the fourth silicon wafer may includefeatures of one or more second silicon heat sinks thereon. The featuresmay include an opening on each of the one or more second silicon heatsinks. The opening may communicatively connect a first primary side anda second primary side of the second silicon heat sinks opposite thefirst primary side. The opening of each of the one or more secondsilicon heat sinks may be aligned with the opening of a respective oneof the one or more first silicon cover plates.

In at least some embodiments, the fourth silicon wafer may includefeatures of one or more second silicon heat sinks thereon. The featuresmay include a plurality of second grooves that form a plurality ofsecond fins on a primary side of each of the one or more second siliconheat sinks facing away from and not contacting a respective one of theone or more first silicon cover plates.

In at least some embodiments, in forming features of the one or morefirst silicon cover plates on the first silicon wafer, forming featuresof the one or more second silicon cover plates on the second siliconwafer, and forming features of the one or more first silicon heat sinkson the third silicon wafer, process 800 may form electrically-conductivefeatures on each of the one or more first silicon cover plates, each ofthe one or more second silicon cover plates, and each of the one or morefirst silicon heat sinks such that the respective electronic device ineach of the one or more silicon heat-dissipation packages is configuredto be powered by an external power source through theelectrically-conductive features on the respective first silicon coverplate, the respective second silicon cover plate, and the respectivefirst silicon heat sink.

Example Applications

Various embodiments of the silicon heat-dissipation package describedherein, and any variations thereof, may be implemented in a wide varietyof applications including, but not limited to, portable electronicsapplications. For example, a silicon heat-dissipation package asdescribed herein may be used in a portable electronics apparatus such asa tablet computer (e.g., iPad by Apple of Cupertino, Calif.), hand-heldmobile communication device (e.g., iPhone by Apple of Cupertino,Calif.), notebook/laptop computer, portable medical device, portablelighting device, portable laser device, or any suitable hand-heldportable device.

Additionally, various embodiments of the silicon heat-dissipationpackage, and any variations thereof, may be implemented in anon-portable electronics apparatus. For example, a siliconheat-dissipation package as described herein may be used in aillumination device, lighting instrument, laser device, wirelesscommunication device, telecommunication device, medical device, desktopcomputer, server, network node such as a router, switch, gateway or thelike, etc.

Additional and Alternative Implementation Notes

The above-described embodiments pertain to a technique, design, scheme,device and mechanism related to heat dissipation for compact electronicdevices using a silicon package. Although the embodiments have beendescribed in language specific to certain applications, it is to beunderstood that the appended claims are not necessarily limited to thespecific features or applications described herein. Rather, the specificfeatures and applications are disclosed as example forms of implementingsuch techniques.

In the above description of example implementations, for purposes ofexplanation, specific numbers, materials configurations, and otherdetails are set forth in order to better explain the invention, asclaimed. However, it will be apparent to one skilled in the art that theclaimed invention may be practiced using different details than theexample ones described herein. In other instances, well-known featuresare omitted or simplified to clarify the description of the exampleimplementations.

The described embodiments are intended to be primarily examples. Thedescribed embodiments are not meant to limit the scope of the appendedclaims. Rather, the claimed invention might also be embodied andimplemented in other ways, in conjunction with other present or futuretechnologies.

Moreover, the word “example” is used herein to mean serving as anexample, instance, or illustration. Any aspect or design describedherein as “example” is not necessarily to be construed as preferred oradvantageous over other aspects or designs. Rather, use of the wordexample is intended to present concepts and techniques in a concretefashion. The term “techniques,” for instance, may refer to one or moredevices, apparatuses, systems, methods, articles of manufacture, and/orcomputer-readable instructions as indicated by the context describedherein.

As used in this application, the term “or” is intended to mean aninclusive “or” rather than an exclusive “or.” That is, unless specifiedotherwise or clear from context, “X employs A or B” is intended to meanany of the natural inclusive permutations. That is, if X employs A; Xemploys B; or X employs both A and B, then “X employs A or B” issatisfied under any of the foregoing instances. In addition, thearticles “a” and “an” as used in this application and the appendedclaims should generally be construed to mean “one or more,” unlessspecified otherwise or clear from context to be directed to a singularform.

1. A device, comprising: a first silicon cover plate having a first primary side and a second primary side opposite the first primary side thereof; and a second silicon cover plate having a first primary side and a second primary side opposite the first primary side thereof, the first primary side of the second silicon cover plate including an indentation configured to accommodate an electronic device therein, the first primary side of the second silicon cover plate configured to mate with the second primary side of the first silicon cover plate when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 2. The device of claim 1, wherein the electronic device is bonded to the second silicon cover plate by thermally-conductive epoxy or solder when the electronic device is accommodated in the indentation of the second silicon cover plate.
 3. The device of claim 1, wherein the first silicon cover plate includes an opening communicatively connecting the first primary side and the second primary side of the first silicon cover plate, the opening aligned with the electronic device and exposing at least a portion of the electronic device when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 4. The device of claim 3, further comprising: a collimation element disposed in the opening of the first silicon cover plate and over the electronic device when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 5. The device of claim 4, wherein the collimation element comprises a lens made of glass, silicone, quartz, or polymer.
 6. The device of claim 1, wherein the second primary side of the first silicon cover plate includes first and second metallic patterns deposited thereon and configured to electrically connect to first and second electrodes of the electronic device, respectively, when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 7. The device of claim 6, wherein the second silicon cover plate further includes first and second vias on first and second sides of the indentation, respectively, the first and the second vias filled with an electrically-conductive material and corresponding to the first and the second metallic patterns on the first silicon cover plate to electrically connect to the first and the second metallic patterns, respectively, when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 8. The device of claim 7, further comprising: a first silicon heat sink having a first primary side and a second primary side opposite the first primary side thereof, the first primary side of the first silicon heat sink configured to mate with the second primary side of the second silicon cover plate when the first silicon heat sink and the second silicon cover plate are joined together.
 9. The device of claim 8, wherein the first primary side of the first silicon heat sink includes first and second electrodes deposited thereon and corresponding to the first and the second vias of the second silicon cover plate to electrically connect to the electrically-conductive material in the first and the second vias when the first silicon heat sink and the second silicon cover plate are joined together.
 10. The device of claim 9, wherein the second primary side of the second silicon cover plate includes third and fourth metallic patterns deposited thereon and configured to electrically connect to the first and the second electrodes of the first silicon heat sink, respectively, when the first silicon heat sink and the second silicon cover plate are joined together.
 11. The device of claim 9, wherein the first electrode of the first silicon heat sink extends toward a first distal end of the first silicon heat sink and includes one or more first protrusions configured to electrically connect to an external circuit board, and wherein the second electrode of the first silicon heat sink extends toward a second distal end of the first silicon heat sink opposite the first distal end and includes one or more second protrusions configured to electrically connect to the external circuit board.
 12. The device of claim 8, wherein the second primary side of the first silicon heat sink includes a plurality of first grooves that form a plurality of first fins on the second primary side of the first silicon heat sink.
 13. The device of claim 1, further comprising: a second silicon heat sink having a first primary side and a second primary side opposite the first primary side thereof, the second primary side of the second silicon heat sink configured to mate with the first primary side of the first silicon cover plate when the second silicon heat sink and the first silicon cover plate are joined together.
 14. The device of claim 13, wherein the first primary side of the second silicon heat sink includes a plurality of second grooves that form a plurality of second fins on the first primary side of the second silicon heat sink.
 15. The device of claim 13, wherein the first primary side of the first silicon cover plate includes a metal layer deposited thereon and configured to bond the first silicon cover plate and the second silicon heat sink.
 16. A device, comprising: a first silicon cover plate having a first primary side and a second primary side opposite the first primary side thereof; a second silicon cover plate having a first primary side and a second primary side opposite the first primary side thereof, the first primary side of the second silicon cover plate including an indentation configured to accommodate an electronic device therein, the first primary side of the second silicon cover plate configured to mate with the second primary side of the first silicon cover plate when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween; a first silicon heat sink having a first primary side and a second primary side opposite the first primary side thereof, the first primary side of the first silicon heat sink configured to mate with the second primary side of the second silicon cover plate when the first silicon heat sink and the second silicon cover plate are joined together; and a second silicon heat sink having a first primary side and a second primary side opposite the first primary side thereof, the second primary side of the second silicon heat sink configured to mate with the first primary side of the first silicon cover plate when the second silicon heat sink and the first silicon cover plate are joined together.
 17. The device of claim 16, wherein the first silicon cover plate includes an opening communicatively connecting the first primary side and the second primary side of the first silicon cover plate, the opening aligned with the electronic device and exposing at least a portion of the electronic device when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween, wherein the second silicon heat sink includes an opening communicatively connecting the first primary side and the second primary side of the second silicon heat sink and aligned with the opening on the first silicon cover plate, and wherein the device further comprises: a collimation element disposed in the opening of the first silicon cover plate and over the electronic device when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween.
 18. The device of claim 16, wherein the second primary side of the first silicon cover plate includes first and second metallic patterns deposited thereon and configured to electrically connect to first and second electrodes of the electronic device, respectively, when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween, wherein the second silicon cover plate further includes first and second vias on first and second sides of the indentation, respectively, the first and the second vias filled with an electrically-conductive material and corresponding to the first and the second metallic patterns on the first silicon cover plate to electrically connect to the first and the second metallic patterns, respectively, when the first silicon cover plate and the second silicon cover plate are joined together with the electronic device sandwiched therebetween, wherein the first primary side of the first silicon heat sink includes first and second electrodes deposited thereon and corresponding to the first and the second vias of the second silicon cover plate to electrically connect to the electrically-conductive material in the first and the second vias when the first silicon heat sink and the second silicon cover plate are joined together, and wherein the second primary side of the second silicon cover plate includes third and fourth metallic patterns deposited thereon and configured to electrically connect to the first and the second electrodes of the first silicon heat sink, respectively, when the first silicon heat sink and the second silicon cover plate are joined together.
 19. The device of claim 16, wherein the second primary side of the first silicon heat sink includes a plurality of first grooves that form a plurality of first fins on the second primary side of the first silicon heat sink, and wherein the first primary side of the second silicon heat sink includes a plurality of second grooves that form a plurality of second fins on the first primary side of the second silicon heat sink.
 20. The device of claim 16, further comprising: the electronic device accommodated in the indentation of the second silicon cover plate and sandwiched between the first and the second silicon cover plates, wherein the electronic device is at least partially configured to function as a light-emitting diode (LED), a laser diode, a radio frequency (RF) chip, a microwave chip, a photodiode, or a sensor. 21-42. (canceled) 